greymarketresearch super safety

[Deerhurst]

Are you using an unmodified detent pin?

From GMR website:

"Bolt bounce in Super Safety mode is another common occurrence and is frequently misdiagnosed as “light primer strikes” or the assumption that the trigger or hammer didn’t reset, and the hammer just rode the bolt into battery.

General tips : use the included detent , the domed side of the stainless detent goes up facing the Push Button Safety . Do not modify the detent, do not use an unmodified cone shaped OEM detent, do not cut the safety selector spring. The Push Button Safety should require some effort to switch from fire/SS/safe. It should not feel mushy or be able to switch positions on its own while shooting."

More problems fixes here.

Common Issues & Problems

greymarketresearch.net

I have not yet fired a single round with a SS installed. Bolt bounce cannot be the problem. I've tried pretty hard to make it clear I have not yet made it to the range to put any rounds through it and all issues have been found during function testing on the bench.

Using GMR's detent.

I am modifying the printed trip. The slot the SS lever sits in appears to be too loose. I have tightened the slot by 0.040 so far and have found some improvement. If I'm aggressive with cycling the action I can get it to work. Sometimes. If I'm gentle it does not work.

It almost appears that the trip does not move far enough rearwards. I'm going to do this in sections. Adding 0.020" to the front surface where the bolt contacts to pull the trip rearward and then pull 0.100" off the overall length at the rear behind the trip slot. I am also going to loosen the front edge, edge that hits the hammer side of the lever, by 0.020 to try to give the hammer more time to go home before the drum tries to put a force on the trigger. I'm almost wondering if the lever is being activated before the hammer is fully depressed. The lever won't move until the hammer is held by the disconnectors.

It's got something to do with the timing of when the lever gets hit and when the hammer is fully depressed.

My laptop is doing a chkdsk /r (175299 of 1136368 down!) due to windows being stupid. If it were not for solid edge I would run Linux. This could be a while. If I get a geometry that works I will find a place to host the 3MF.


I need a clear lower. Would make life so much easier!

 

[Deerhurst]

Looking at it more it appears the trip hits the lever before the hammer hits the disconnector. The lever cannot move until the hammer is completely captured by the disconnector.

Working on finding the right spacing without being too weak and without getting in the way of the hammer. Gotta move the hammer far enough before the lever gets hit.

 

[Deerhurst]

Figured it out!

The lever was being hit by the trip before the hammer was fully depressed and held by the disconnector. In SS mode the lever/tumber assembly cannot move until the hammer is fully depressed and caught by the disconnector.

My mods to the 3D printed trip was moving the front of the trip slot forward 0.050" (thinner wall now) and i removed ~0.040" from the shoulder that the bolt hits to move the trip rearward. I did the shoulder mod with an exacto knife so I'll update that on the drawing sometime tomorrow. Laptop is back to chkdsk that I interrupted earlier.


I'll clean up the model a bit and put a copy on some host. I think I have an Odyssey account.

 

[Deerhurst]

Range report.


Runs awesome in 556. I'd say somewhere between 700 and 800RPM. Quite controllable. Easy doubles and triples.


In 22LR it gets a little more interesting. Ran perfect about 70% of the time. Every couple mags it would rip for about half a mag then light strike so probably bolt bounce going on. I forgot my insert to add weight. Could also be that the CMMG kit probably hasn't been cleaned in at least 1000 rounds. Maybe double that. Was getting light strikes in semi too.

When it runs in 22LR it absolutely rips! I'd say 1300-1500RPM. Ridiculous fun!


I need to delay the trip a little more with latest trip. The modified via Razer blade one worked fine. The printed one didn't run.

 

[Offmarksman]

Question, I was playing with one today, and dry firing it when in semi mode, if you keep the trigger depressed, and cycle the bolt, when you release the trigger, it releases the hammer. Essentially a binary trigger, any ideas on how to correct this?

 

[Deerhurst]

Is your disconnector worn? The SS cannot make the FCG do that that I have found. All it does is lock the trigger out.


Cleaned the CMMG kit and installed a small weight. Didn't know that much gunk could be on such a small object! Ran a pipe cleaner down the FP channel and found a spring in what I thought was a pile of black junk on the pipe cleaner! I bet it runs much differently now. I'm going with probably 2000+ rounds since the last cleaning. Maybe 3000+ as I just remembered a buddy of mine and I fed mags to some kids and their dad down at shooting pit and fed them at least 1000 rounds of 22 on a binary trigger. I've run it enough over it's life I've basically worn all of the phosphate off any surface that runs on another surface. Rain the next few days so I'll have to plan a time when it's mostly dry to get out and test it again. Maybe the ROF will go up!

 

[Offmarksman]

I will try a new one, and see if makes any difference. I suspect that the disconnect or is not engaging with the hammer because the trigger is not profiled correctly for the SS. Will play around with it and report back in a few days. Thanks!!!

 

[Alaska_Shooter]

I think it works better in 22lr than my $$$$$ M-16 🤣

 

[strobro32]

Alsaka_Shooter,

What trip are you using for the SS/CMMG 22LR kit?

 

[Slowmo]

I shot a CMMG Banshee MkG .45 ACP 5" pistol with a Super Safety this morning. Worked like a charm. I will need more than 13 round Glock 21 mags. KRISS 30 rd mags extensions ordered.

10 rounds, 751 RPM.

https://flic.kr/p/2qjfAGY

Did you have to do anything special to get the CMMG to work?

 

[strobro32]

No.

But I do have 1 or 2 FTF every 30 rd mag. And the last 2 times I was out shooting the ROF jumped to 840 RPM. Not sure why that is. Same ammo was used.

 

[Alaska_Shooter]

I used a Bore Buddy trip with the 22lr

 

[Deerhurst]

No.

But I do have 1 or 2 FTF every 30 rd mag. And the last 2 times I was out shooting the ROF jumped to 840 RPM. Not sure why that is. Same ammo was used.

22LR does 22LR shenanigans. I need to get out and try mine with the clean CMMG and a small carbide weight. Carbide because I have broken endmills. Might as well do something.


I dont remember the rules and such for linking to files here. Give me a heads up if NoGo.

Here is my modified trip in 3MF format. The OAL is a little shorter, the top is clearanced so no trimming to the SS lever and I delayed the timing a but to make sure the hammer is all the way reset and captured by the disconnector before the lever moves. I have not explicitly tried the printed version of this model though it is in my 22LR upper. It is a modified copy of the original trip model I found on Odysse and has been modified to match my hand adjusted trip when printed on my printer. Hope it helps anyone who is having the same issues I was!

SS CMMG Trip

Ill get it out to the range and test it again hopefully soon.

 

[strobro32]

My 3D printed GMR 22LR paddle and GMR 3D printed 22LR trip took a dump this last range visit. GMR ships 2- 3D printed paddles with the 22LR kit so I suppose they know the lifespan of the 3D printed lever is limited. Sad because it worked really well for about 4-5 hundred rounds.

I'm also having reliability issues with the metal BB 22LR trip and GMR SS metal lever. It works and then within a mag or two, the combo starts to have hammer follow on a chambered live 22LR round.

 

[root]

My 3D printed GMR 22LR paddle and GMR 3D printed 22LR trip took a dump this last range visit. GMR ships 2- 3D printed paddles with the 22LR kit so I suppose they know the lifespan of the 3D printed lever is limited. Sad because it worked really well for about 4-5 hundred rounds.

I'm also having reliability issues with the metal BB 22LR trip and GMR SS metal lever. It works and then within a mag or two, the combo starts to have hammer follow on a chambered live 22LR round.

Strobo are the 3d printed paddles something that can be machined out of steel? Or if not they could possibly be cast from a print.

Or is it something that is supposed to wear fast & be replaced to save the other parts?
I'm currently waiting on just the LeePercission AR lower for the SP5 to arrive last part I need to try out that setup.
Figured I might try the SS in either the DPMS upper or the Colt 9mm carbine while I wait and see if it works either of those and if not what will need to be done to make it work. If I get time.
Hunting season is here and I plan on shooting a few critters in the next few weeks.

 

[strobro32]

GMR makes the paddles out of steel. IDK why the GMR 22 LR paddles are 3D printed. Maybe to have less wear on their 22LR 3D printed trips.
Borebuddy's 22LR metal trip was designed for GMR's steel lever. I'm still trying to work out the reliability issues with that combo.

I'm sure the GMR 3D printed levers trips could be molded cast but shrinkage happens with casting epoxy, resin or metal. I'm not going down that rabbit hole because I just got a library card and the local library has a 3D printer.

I'm still hoping someone will design and make a trip for the S&W 15-22 system. That would be great as the 15-22 is a more reliable 22LR system to begin with.

 

[root]

7% on resin most everything else is 7% - 12% when cast I have a foundry book I could look in to see how much over zinc would be.
Softer then most metals way harder then average pla or pla+.
Won't wear on other metal parts and low melting point just over lead @ around 800f of so.
I've done a whole lot of casting with resin, metal, and up to bronze.
Also kinda wonder how one would hold up made from oilite bronze since that's self lubricating.
I'll def be rereading this thread from page 1 one once I have the time to really mess with this stuff a few hrs a day.
I have a long road ahead since none of my machines are setup and have only gotten setup as needed.
Forced to setup the 20 ton press last week due needing to press wheel bearing.

 

[Deerhurst]

With a resin printer you can oversized a mold by 7% and cast them.

 

[Hey...]

With a resin printer you can oversized a mold by 7% and cast them.

Just a note I find +1.5% is what I scale from a CAD file to the Cura slicer when casting aluminum from a 3D print. Don’t want to derail this thread, just pointing out my findings on what I said.

 

[Deerhurst]

Just a note I find +1.5% is what I scale from a CAD file to the Cura slicer when casting aluminum from a 3D print. Don’t want to derail this thread, just pointing out my findings on what I said.

Good info especially if someone wants to do a lost resin or lost PLA mold. There are resins designed for this for resin printers.